The field of the disclosure relates generally to electric motors, and more specifically, to systems and methods for determining a loss of phase condition for a phase of three-phase input power provided to an electric motor controller.
At least some known three-phase electric motors start by receiving three-phase power, but lose a phase or suffer a voltage drop on a phase after startup. Such motors typically continue to operate but will run at higher temperatures and/or receive higher input current at a controller of the motor. Such a loss of phase condition may destroy winding insulation and/or shorten the life expectancy of electronic components such as direct current (DC) bus capacitors, ultimately burning out the motor and may only take a few minutes to occur. Accordingly, detection of input phase loss may also be used to trigger an alarm or fault for safe continued operation or shutdown. Conventional phase loss detection techniques, however, are generally either complicated and costly or unable to adequately detect all phase loss conditions.